Hello to everyone. I am new here. I created my account and started working to contribute to this open source map system. However, the satellite images of my city are 3 years ago.
For this reason, many streets, parks and business centers that currently exist in the city I live in do not appear on the map. Do I have the option to update satellite images of my city? Can you inform about this?
Indeed, we don’t have satellite images of our own, so we rely on what providers make available for us to legally use while mapping. Often there are several layers available for a location, so if that’s the case, check if one of them may be more recent. (There’s frequently a trade-off between recent updates, high resolution, good accuracy, and other desirable traits.) Unfortunately, not having an imagery source more recent than a few years isn’t unusual.
If you can convince someone who has better images to allow them to be used for OSM mapping, that would be great of course! But be aware that making such an arrangement legally water-tight can be tricky.
Some people are also using drones and such for making images, but that hasn’t gone beyond a few small-scale experiments.
I understand. Unfortunately, it is very difficult for us to get new satellite images. Well, would it be a problem if we instead add roads and areas that are not in the openstreet system to fit the truth? For example, there is now a park where it appears as land on the system, and I mark it and show it as a park. I also do this for roads.
I have never done this until now, but if you approve, I will update all the details in my living place to be the most accurate. Say what?
There is nothing wrong with ‘guesstimating’ the alignment of roads & parks from your local knowledge. Although they may not be geographically accurate if their relationships with each other are right the data is still useful. You can then use a GPS track for more accurate alignment. Lower resolution satellite imagery can be used to outline landscape features (lakes, forests, urban areas). Larger roads and open spaces may be visible on much more recent satellite imagery of a lower resolution (Sentinel Cloudless, Landsat) which can be accessed using the JOSM editor. The online editor iD is not really designed to support this type of usage.
The important principle is that OSM is iterative. When better quality information is available the map data can be improved step-by-step. Even if the data is not absolutely precise it can often be useful.
A few words about rules-of-thumb when trying to locate features without imagery or GPS. Residential streets are often a fairly predictable distance from each other. The distance will vary from country to country and from type of urban area. For instance in much of Latin America streets are laid out in a grid spaced approximately 100 m. Local knowledge of the type and age of urban development can be used to build-up these rules of thumb (and you can check for areas where imagery is available). OpenCycleMap shows contours (it is available in some editors) and these can greatly help feature alignment if any of the terrain you are mapping is hilly. It is also often good for rivers and other watercourses.
The key thing is to be aware that it is not permitted to take information from other maps such as Google Maps. Use local knowledge & such satellite images as are available only.
If you are willing you could mention where you are located and perhaps others with experience of using some of the other sources could help.